Carbon Dioxide → 5-Amino-alpha-phenyl-1,2,4-oxadiazole-3-acetic acid

HRID 1657370Notes

Reaction equation

HRID 1657370 reaction equation
C([Li])CCC.[NH2:6][C:7]1[O:11][N:10]=[C:9]([CH2:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)[N:8]=1.O1CCCC1.[C:24](=[O:26])=[O:25]>CCCCCC>[NH2:6][C:7]1[O:11][N:10]=[C:9]([CH:12]([C:13]2[CH:14]=[CH:15][CH:16]=[CH:17][CH:18]=2)[C:24]([OH:26])=[O:25])[N:8]=1

Participants

6

Reactant 4

HCID 280Carbon DioxideHCID 8028TetrahydrofuranHCID 122081793-Benzyl-1,2,4-oxadiazol-5-amineHCID 178418339Butyllithium

Product 1

HCID 215332285-Amino-alpha-phenyl-1,2,4-oxadiazole-3-acetic acid

Reagents, catalysts & solvents 1

HCID 8058HexaneSolvent

Procedure

260 g. (0.507 mole + 20%) of a 15% solution of butyl lithium in n-hexane is cooled to -60° under nitrogen. At this temperature a solution of 27.6 g. of 5-amino-3-(phenylmethyl)-1,2,4-oxadiazole in 300 ml. of absolute tetrahydrofuran is added dropwise with stirring over a period of about 21/2 hours. The reaction mixture is stirred for an additional 30 minutes. Then over a period of 2 hours a proportionate stream of carbon dioxide is passed through the mixture. The cold bath is removed and the reaction mixture is permitted to come to room temperature. This mixture is concentrated in a rotary evaporator, the residue is treated with water and adjusted to pH 8. The aqueous solution is extracted with ether and the aqueous phase is acidified with 2N hydrochloric acid. The precipitate is filtered under suction and reprecipitated twice by dissolving in dilute sodium hydroxide solution and acidifying with dilute hydrochloric acid. 7.4 g. of 5-amino-α-phenyl-1,2,4-oxadiazole-3-acetic acid are obtained, m.p. 163°-164° (dec.).

Workup

  1. stirringThe reaction mixture is stirred for an additional 30 minutes
  2. customThe cold bath is removed
  3. customto come to room temperature
  4. concentrationThis mixture is concentrated in a rotary evaporator
  5. additionthe residue is treated with water
  6. extractionThe aqueous solution is extracted with ether
  7. filtrationThe precipitate is filtered under suction
  8. customreprecipitated twice
  9. dissolutionby dissolving in dilute sodium hydroxide solution

Sources & evidence

ORD record
ord-e101357495fd4d3db2f4e7e30b5ee7f4
Source dataset
uspto-grants-1976_06
Patent number
US03960849

Reaction notes

Loading…